The shear bolt is in place to protect the gearbox from damage. The shear bolt is designed to shear when the blade impacts foreign objects that it is not designed to cut through. To avoid shear bolt failure, engage the PTO slowly at low engine RPM. Shear bolt should be replaced with Grade 2 bolt.
Ensure that your cutter is being engaged and disengaged at an idle speed. Check that the tractor has a hydraulic engage oil clutch. Blades may also need to be reshimmed. The mower blades need to be less than ¾” deflection.
The cutting blades could be out of balance. Be sure to replace both cutting blades at the same time. Not replacing both blades could result in premature bearing damage or structural damage to gearbox or deck.
Dishpan could be out of balance. Check the integrity of the dishpan. Make sure it does not have any damage.
Lowering the cutter to the ground too fast can cause the tailwheel support to fail. The rate of drop on some tractors can be adjusted. Backing up when the cutter is in a ditch can also cause the tailwheel support to fail.
A step by step procedure is located in the Operator’s Manual (manual can be found on Related Products Page below). It is imperative that this be done prior to operation and any time the unit has set idle.
It varies with the gpm and pressure of the power unit and which one of the three motors that is on the unit. There is a charge located in the specifications page in the Operator’s Manual (manual can be found on Related Products Page below).
Do I have to use the third line and what’s the purpose of the line?
Yes, it is recommended that the case drain line be used. If it is not, you run the risk of blowing an output seal as the spike pressures during shut down are too great. The purpose of this line is a case drain. It relieves pressure from the case of the motor when they become greater than the seals can hold.